Gas-burner head with high-pressure air jets



Sept. 11, 1951 R. JENNY GAS BURNER HEAD'WITH HIGH-PRESSURE AIR JETSFiled April 9, 1948 Patented Sept. 11, 1951 I i AIR g Rudolf Jenny,Zurich, Switzerland, assig'nor to JET Meyerhofer G. m. b. H .,1Zurich,jSwitzerland Application April 9, 1948, Serial No. 20,132

My present invention relates to a gas-burner in which the gas flowsthrough a nozzle-shaped conduit, and the air flows into the gasstreamunder a higher pressure than the gas-at the discharge opening ofthe said conduit through a plurality of bores provided in theconduit-wall.

The main requirements to be fulfilled by a gas-burner of the typeindicated are: theexcess air, i. e. the secondary air which does notparticipate in the combustion process as does the primary air, shall bea minimum; the combustion has to be complete and has to take place in aminimum of space; and the range for regulating the rate of combustionshall be large,

In the case of burners of larger size known in the art, the saidrequirements only could be fulfilled by using premixing chambers ordiaphragms. Burners including a premixing chamber are subject toexplosions, while diaphragms bring about a substantial loss of pressureand an overheating of the burners.

In order to avoid such deficiencies and drawbacks, the burner accordingto my present invention comprises, a plurality of bores, disposed inconcentric circles, in the wall of the mouth of the gas conduit for thepassage of air and inclined with respect to the axis of the said conduitso as to give rise to intersecting whirl air currents which interminglewith the diffusing gas stream discharged from the said mouth. To suchend, in a preferred embodiment, the axes of the bores in one circle aredeflected in plan with respect to their appurtenant radii by a uniformsmall acute angle to one side of the radii, and the axes of the bores inthe circle or circles adjacent to the said first circle are deflected inplan with respect to their appurtenant radii by a like angle to theother side of the radii. In elevation, the axes of the bores in adjacentcircles are inclined at difierent vertical angles to the axis of thesaid conduit. The bores in adjacent circles, further, are staggered.

By virtue of the arrangement of the air-passage bores according to mypresent invention, the air discharged into the gas stream, and thus alsothe gas, are thoroughly and intimately mixed so as to obtain perfectcombustion with a minimum of excess air and in a minimum of space.

One form of invention is shown, by way of example, in the accompanyingdrawing, in which:

Fig. 1 is a vertical section;

Fig. 2 a top plan view, and

Fig. 3 a perspective top plan view for illustrating the directions ofthe air streams discharged from the inner circle of bores.

1 Claim. (Cl. 158 -116) The burner shown comprises a nozzle-shapedconverging gas conduit I through which the gas flows as indicated by therespective arrow in Fig. 1. The exit end of conduit I is sharply flaredoutward, i. c. it forms a wide-angle difiusor cone. The air enters intothe burner through the conduit 2, as indicated by the respective arrowin Fig. 1, and then flows into the gas stream through a series of bores3 and 4 provided in the'wall of the difiusor cone. The air, being undera higher pressure than the gas, carries the gas onward byinjector-action upon being discharged from the said bores 3 and 4.

The arrangement of the latter with respect to the axis of conduit I andto each other is as follows:

Seen in plan, Fig. 2, the axes of the air streams discharged from theinner circle of bores 3 (empty arrows) are deflected to one side oftheir appurtenant radii by a small acute angle of uniform size; whilethe axes of the air streams discharged from the outer circle of bores 4(full arrows) are deflected to the other side of their appurtenant radiiby a uniform angle of substantially equal size as in the case of the airstreams from the bores 3. The points of intersection of consecutiveempty 'arrows and full arrows, respectively, define an inner and anouter circle respectively, the said two circles being situated in twoplanes at right angles to the axis of conduit I, as is evident from Fig.l.

Seen in elevation (Fig. 1) the axes of the air streams discharged fromthe inside bores 3 (empty arrows) are inclined at a uniform angle withrespect to the axis of conduit I, while the axes of the air streamsdischarged from the outside bores i (full arrows) are more steeply inclined. The full arrows, as well as the empty arrows, appear tointersect on the axis of conduit I, which, however, they do not, as isevident from g- 2 The said bores 3, 4 are disposed in two circles, thecenters of which are situated on the axis oi conduit I, and the bores ofone circle are staggered relative to those of the other circle.

The air streams discharged from each circle of bores. thus, define awhirl path or vortex coaxial with the axis of the gas stream dischargedfrom conduit I or, respectively, from the difiusor cone of the latter.The said whirl paths or vortices have a different pitch and rotate inopposite directions. In Fig. 3, the air streams discharged from thebores 3 are shown in form of pencils defining a whirl path ofcounterclockwise rotation.

The air entering into the burner through conduit 2, may be preheated.Since the gas flows into the burner through a conduit 1 of comparativelylarge cross-section, as well as at a comparatively low velocity,non-purified gas may be used without running the risk of choking up thesaid conduit.

The injector-action of the air streams discharged from the bores 3 and 4enables the gas to be supplied at a comparatively low pressure.

What I claim as new, and desire to secure by Letters Patent, is: W W A gA gas burner comprising means for forming an upwardly converging gasoutlet having an outwardly and upwardly flaring discharge end, meansforming an air chamber annularly surrounding the gas outlet, and aplurality of bores extending through the said discharge end from the airchamber to the gas outlet, the axes of said bores being inclined withrespect to the vertical axis of the gas outlet, and means supplying airto said chamber at a pressure exceeding the gas pressure in said gasoutlet means, the improvement defined by arranging the said bores atequal spacings in at least two circular rows of which the centers aresituated in the axis of the gas outlet, the bores of one row beingstaggered relatively to those of the other row and having a differentaxial inclination, the axes of each two adjacent bores 01 one rowintersecting in points which define a first circle of which the centeris situated on the gas outlet axis, and the axes of each two adjacentbores of the other row intersecting in points which define a secondcircle of which the center also is situated in the gas outlet axis, thesaid two circles lying in two planes which are at right angles to thegas outlet axis; the axes of the bores in one row being directed,relative to the circumferences of the circles, in opposite directions,the whole being for the purpose of setting up in the air stream enteringthe gas stream at least two whirl paths coaxial with the axis of the gasoutlet and of opposed directions with a view of intimately mixing theair with the gas.

RUDOLF JENNY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,790,927 Kreager Feb. 3, 1931FOREIGN PATENTS Number Country Date 749,423 France L--. May 8, 1933

